This invention relates to drop marking systems for products sold in cans and bottles, such as beer, soft drinks, food stuffs and the like. More specifically, it relates to an apparatus for removing water from an area to be marked just prior to the marking operation. Dewatering, as this step is commonly called in the industry, is employed to permit typical marking systems such as ink jet coders to print information on a bottle or can passing by an ink jet print head during the bottling or canning process. Such marking operations typically place important information on the product, such as date codes, lot information and similar information used to track the product for various purposes.
The present invention has particular application to the beverage industry where cans and bottles of chilled drinks, such as beer, soda and the like are placed into cans or bottles by high speed filling equipment. Shortly after the filling operation, capping and labeling operations take place followed by the marking operation to specify a date of manufacture and/or manufacturing codes. Proper coding is an important consideration if it should be necessary to trace the product to a particular assembly line or batch. It is difficult to ensure completely accurate marking of bottles and cans due mainly to the condensation which forms on the outside of the container after the addition of the cold liquid. Additional problems are encountered due to soapy type lubricants used on the product conveyors. If these liquids are not removed from the area of the container to be coded, the ink from the ink jet printer or similar drop marking device, will not adhere satisfactorily to the container.
Present efforts to solve this problem include the use of air manifolds positioned immediately adjacent the ink jet print head. Generally, such manifolds consist of a closed section of pipe connecting to an air supply. Small holes are provided along the length of the pipe. Air passes through the holes and is directed at the bottles or cans in an effort to blow off the undesired liquid. Such prior art designs use more air than necessary, are fairly noisy and still do not produce an area as clean and dry as is desired for high reliability marking of the containers.
A further problem with prior art systems is the nature of the air blast. High pressure air, if not precisely positioned can interfere with label placement and adhesion on the containers being marked. More specifically, front and back labels are often applied to the containers and the water based adhesive used requires a period of time to set. Air blasts, for purposes of dewatering, can dislodge or shift these labels.
It is accordingly an object of the present invention to provide an improved dewatering apparatus which can effectively remove moisture from the area of a container to be marked while the container is moving on a high speed beverage filling conveyor.
It is another object of the invention to provide a dewatering system which can be positioned to dewater only the area to be marked and which will avoid interfering with the adhesion of recently applied labels to the container.
A further object of the invention is to provide an apparatus employing at least one air knife to precisely direct air at the container to be marked to ensure that a clean, dry surface is presented to the marking device.
These and other objects of the invention will be apparent from the remaining portion of the specification.